Fix accidental revert of HADOOP-13072: WindowsGetSpaceUsed constructor should be public (Vinayakumar B via cmccabe)

(cherry picked from commit 975786492c42b8aebc6dc247bdcdb4768d99d641)
(cherry picked from commit e751bb4497879d66ec771e6f9e08937a3164516b)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/WindowsGetSpaceUsed.java

@@ -31,7 +31,8 @@ import java.io.IOException;
 @InterfaceStability.Evolving
 public class WindowsGetSpaceUsed extends CachingGetSpaceUsed {
 
-  WindowsGetSpaceUsed(CachingGetSpaceUsed.Builder builder) throws IOException {
+  public WindowsGetSpaceUsed(CachingGetSpaceUsed.Builder builder)
+      throws IOException {
     super(builder.getPath(),
         builder.getInterval(),
         builder.getJitter(),